How long are the email codes valid?

Both codes are 6 digits, and both are short-lived on purpose — a code sitting in a mailbox for a week is a way in for anyone who reads that mailbox later.

• Email confirmation code (sign-up): 10 minutes.
• Password reset code: 15 minutes.

A code can be used once. If yours has expired, request a new one from the same screen — and use the newest email, since a new request cancels the previous code.